The present invention relates to an apparatus for mixing liquids, and particularly an apparatus for mixing paints in closed containers.
In the prior art, a number of techniques have been utilized for physically shaking a paint container in order to obtain a homogeneous, uniform color paint where the pigment has separated from the vehicle or where it is desired to mix a primary pigment paint color with a base paint. These devices generally operate on the principal of shaking the container in an oscillatory manner about the paint container axis, or about an axis which is normal to the paint container axis. However, paint mixers have been devised which utilize various mechanisms to impart a vigorous shaking motion to the paint container utilizing a variety of techniques.
For example, U.S. Pat. No. 3,464,675, issued Sept. 2, 1969, describes a motor-driven cam which is connected to a platform mounted on a rocker shaft so as to cause the platform to oscillate about the rocker shaft, and thereby cause a paint container attached to the platform to become oscillated over an angular arc having the rocker shaft as its vertex. U.S. Pat. No. 1,908,561, issued May 9, 1933, describes a paint shaker wherein two containers are vibrated about an axis normal to the container axis. U.S. Pat. No. 3,388,895 issued June 18, 1968, describes an apparatus wherein two paint cans are connected via rods to a single eccentric driving mechanism having a counter weight and wherein the containers are respectively rocked about an axis normal to the container axis.